From f9c16a950d0791aab269b1a5507487d058712421 Mon Sep 17 00:00:00 2001
From: Dirk Baeumer <dirkb@microsoft.com>
Date: Mon, 7 Sep 2020 09:51:56 +0200
Subject: [PATCH] Support for prepare rename default behavior

---
 client/src/common/client.ts     | 14 ++++++++++++++
 protocol/src/common/protocol.ts | 11 ++++++++++-
 2 files changed, 24 insertions(+), 1 deletion(-)

diff --git a/client/src/common/client.ts b/client/src/common/client.ts
index bfeb22ed2..f37b55dae 100644
--- a/client/src/common/client.ts
+++ b/client/src/common/client.ts
@@ -2155,6 +2155,10 @@ class DocumentOnTypeFormattingFeature extends TextDocumentFeature<DocumentOnType
 	}
 }
 
+interface DefaultBehavior {
+	defaultBehavior: boolean;
+}
+
 class RenameFeature extends TextDocumentFeature<boolean | RenameOptions, RenameRegistrationOptions, RenameProvider> {
 
 	constructor(client: BaseLanguageClient) {
@@ -2165,6 +2169,7 @@ class RenameFeature extends TextDocumentFeature<boolean | RenameOptions, RenameR
 		let rename = ensure(ensure(capabilites, 'textDocument')!, 'rename')!;
 		rename.dynamicRegistration = true;
 		rename.prepareSupport = true;
+		rename.prepareSupportDefaultBehavior = true;
 	}
 
 	public initialize(capabilities: ServerCapabilities, documentSelector: DocumentSelector): void {
@@ -2211,6 +2216,10 @@ class RenameFeature extends TextDocumentFeature<boolean | RenameOptions, RenameR
 						return client.sendRequest(PrepareRenameRequest.type, params, token).then((result) => {
 							if (Range.is(result)) {
 								return client.protocol2CodeConverter.asRange(result);
+							} else if (this.isDefaultBehavior(result)) {
+								return result.defaultBehavior === true
+									? null
+									: Promise.reject(new Error(`The element can't be renamed.`));
 							} else if (result && Range.is(result.range)) {
 								return {
 									range: client.protocol2CodeConverter.asRange(result.range),
@@ -2234,6 +2243,11 @@ class RenameFeature extends TextDocumentFeature<boolean | RenameOptions, RenameR
 		};
 		return [Languages.registerRenameProvider(options.documentSelector!, provider), provider];
 	}
+
+	private isDefaultBehavior(value: any): value is DefaultBehavior {
+		const candidate: DefaultBehavior = value;
+		return candidate && Is.boolean(candidate.defaultBehavior);
+	}
 }
 
 class DocumentLinkFeature extends TextDocumentFeature<DocumentLinkOptions, DocumentLinkRegistrationOptions, DocumentLinkProvider> {
diff --git a/protocol/src/common/protocol.ts b/protocol/src/common/protocol.ts
index c0703370c..1b2aae77c 100644
--- a/protocol/src/common/protocol.ts
+++ b/protocol/src/common/protocol.ts
@@ -2596,6 +2596,13 @@ export interface RenameClientCapabilities {
 	 * @since version 3.12.0
 	 */
 	prepareSupport?: boolean;
+
+	/**
+	 * Client supports the default behavior result.
+	 *
+	 * @since version 3.16.0
+	 */
+	prepareSupportDefaultBehavior?: boolean;
 }
 
 /**
@@ -2651,10 +2658,12 @@ export interface PrepareRenameParams extends TextDocumentPositionParams, WorkDon
 
 /**
  * A request to test and perform the setup necessary for a rename.
+ *
+ * @since 3.16 - support for default behavior
  */
 export namespace PrepareRenameRequest {
 	export const method: 'textDocument/prepareRename' = 'textDocument/prepareRename';
-	export const type = new ProtocolRequestType<PrepareRenameParams, Range | { range: Range, placeholder: string } | null, never, void, void>(method);
+	export const type = new ProtocolRequestType<PrepareRenameParams, Range | { range: Range, placeholder: string } | { defaultBehavior: boolean } | null, never, void, void>(method);
 }
 
 //---- Command Execution -------------------------------------------